Perforated card reader



Oct. 25, 1960 J. K. SNELL ETAL 2,957,623

PERFORATED CARD READER Filed Dec. 9, 1957 6 Sheets-Sheet 1 FIG.|

INVENTORSZ J.K|RK SNELL, DONALD F. ROGERS, JOHN M. RHOADES,

THEIR ATTORN Oct. 25, 1960 J. K. SNELL ETAL PERFORATED CARD READER Filed Dec. 9, 1957 6 Sheets-Sheet 2 BYM,

THEIR ATTO EY;

Oct. 25, 1960 J. K. SNELL ETAI. 2,957,623

PERFORATED CARD READER Filed Dec. 9, 1957 6 Sheets-Sheet 3 lNVENTORS J.K|RK SNELL, DONALD F. ROGERS, JOHN M. RHOADES,

BY ma 7?;

THEIR ATTORNEY.

Oct. 25, 1960 J. K. SNELL ETAL 2,957,623

PERFORATED CARD READER Filed Dec. 9, 1957 A 6 Sheets-Sheet 4 \-|e FORWARD 9 '1 86 F IG.6A 94 no us 26 FORWARD l I I INVENTORS 6 20 J. KIRK SNELL,

DONALD F. ROGERS, JOHN M- RHOADES,

BY pad/777A THEIR ATTORNEY.

Oct. 25, 1960 J. K. SNELL ETAL 2,957,623

PERFORATED CARD READER Filed Dec. 9, 1957 6 Sheets-Sheet 5 FIGJB FORWARD INVENTORS J.KIRK SNELL, DONALD F. ROGERS, JOHN M. RHOADES,

BY 21%; k! w THEIR ATTORNEY.

FIG.7A

1960 J. K. SNELL ETAL 2,957,623

PERFORATED CARD READER Filed Dec. 9, 1957 6 Sheets-Sheet 6 FIG-8 FORWARD 96 96 1 94 [Q8 I07- I03 2 l I02 I04 us I00 W ,L j r 28 FIG." I56 SWITCH CONTROL INVENTORSI J.K|RK SNELL,

DONALD E ROGERS, JOHN M. RHOADES,

THEIR ATTORN Y.

United rates 2,957,623 Patented Oct. 25, 1960 Free PERFORATED CARD READER Jacob Kirk Snell, Donald F. Rogers, and John M. khoades, Waynesboro, Va., assignors to General Electric Company, a corporation of New York Filed Dec. 9, 1957, Ser. No. 701,388

13 Claims. (Cl. 235-6111) This invention relates to improvements in devices for sensing perforated cards to derive information represented as the perforations in the cards and to develop electrical signals representative of the information.

An object of this invention is to provide a novel device for sensing perforated cards which is of a relatively simple yet durable construction.

Another object of this invention is to provide a novel apparatus for sensing perforated cards and deriving information represented in the form of perforations the cards without requiring that therelatively delicate sensing means carry electrical currents of any significant magnitude.

A still further object of this invention is to provide a novel apparatus for sensing perforated cards in which the sensing elements are not subjected to excessive strain thereby substantially prolonging their life.

Still another object of this invention is to provide a novel apparatus for sensing perforated cards which has a minimum of moving mechanical parts and relies upon non-contacting electrical and electromagnetic elements to thereby provide a device capable of long life.

Briefly, the objects of our invention are achieved in one embodiment by the provision of a card feeding means which functions to support perforated cards in a hop-per waiting to be sensed and further functions to feed cards to, and support cards in, a position to be engaged and read by perforation sensing elements. Means are provided to move the sensing elements away from the card supporting and feeding means a card is being moved in a direction such as to subject the sensing elements to large stressing forces. Further, magnetic controlled elements are provided in circuits producing electrical signals representative of the information stored in the. cards to insure long life of these elements.

The subject matter which we regard as our invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. Our invention, however, both as to its structure and method operation together with further objects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a side View of a perforated card sensing apparatus incorporating our invention;

Fig. 2 is an exploded cross-sectional side view of the card sensing apparatus;

Fig. 3 is a plan view of the perforated card sensing apparatus showing the card supporting and feeding element in a forward or card sensing position;

Fig. 4 is a view along the line 4--4 in Fig. 3;

Fig. 5 is a view along the line 5-5 in Fig. 3;

Fig. 6A is a fragmentary view along the line 6A in Fig. 4 illustrating a portion of the apparatus in oneposition during its cycle of operation;

Fig. 6B is a fragmentary view along the line 6B in Fig. 4 illustrating a portion of the apparatus in one position during its cycle of operation;

- ing device usable with our invention;

Fig. 7A is a view similar to Fig. 6A illustrating a portion of the invention in another position during its cycle of operation;

Fig. 7B is a view similar to Fig. 6B illustrating the position of the perforation sensing elements in another position during their cycle of operation;

Fig. 8 is a fragmentary view similar to Fig. 6A illustrating the mode of operation of a portion of the apparatus after a card has been sensed;

Fig. 9' is aview in perspective of a form of card retain Fig. 10 is a schematic illustration of an embodiment of a circuit for deriving electrical signals from sensed perforations in the cards; and

Fig. 11 is a schematic illustration of an embodiment of an alternative circuit for deriving electrical signals from sensed perforations in the cards.

Fig. l of the'd'rawing illustrates an assembled perforated card sensing apparatuswhich, in this embodiment, is constituted by a housing or base or support 2.. A front cover 4' is slideable thereon and is provided with a handle 6 for its manipulation. A rear cover 8 is removably attached to the base. In order to make the necessary electrical connections for deriving the electrical signals produced by the sensing elements reading the perforated card and for supplying the necessary electrical energy for the operation of the apparatus, terminals such as shown at 10 may be provided conveniently on the main housing 2.

In Fig. 2 of the drawing, the card sensing apparatus is shown with the front cover 4 removed from the base 2. Provided on the lower portion of the front cover 4' and fitting within space provided in the main housing 2 is a hopper 12 for receiving the perforated cards after they have been sensed in a manner to be described hereinafter. The perforated cards to be sensed. are placed in a storage hopper 14 formed by the vertically extending guides 16 and 18. In this position, the cards rest on a table 20. Means mounting the table 20 for reciprocating movement as seen in Figs. 3 and 4 may take the form of a plurality of rotatable supports 22 which run on a guideway 24 provided on the housing 2. The table 20 is a length whereby when it has moved to a forward position, a portion thereof will extend under the hopper 14 to support the cards. with bearings 26 which encompass a shaft 28 extending longitudinally of the housing 2. Referring again to Fig. 2, means for propelling the table on the longitudinally extending shaft 28 and guides 24 is constituted by a quick return mechanism comprising a slotted lever 30 which has engaged in the upper end of the slot thereof a projection 32 secured to the back end of the table 20. The lever 30 is pivoted on a suitable bearing support 34 and engaging in the slot is boss 36 carried by a sprocket wheel 38. The sprocket wheel is driven by a chain 40 connected between it and a pinion 42. The pinion 42 is connected to the shaft of a suitable motor 44 to be rotated thereby. It may be seen that this apparatus for reciprocating the table 20 constitutes a quick return mechanism in that the forward motion of the table is imparted to it when the boss 36 is rotating on the upper half of the sprocket wheel 38 thus providing a relatively small ratio of lever arms between it and the bearing 34 and between the projection 32 and the bearing 34, while the rearward motion of the table occurs when the boss is rotating on the lower half of the sprocketed wheel as shown in the drawing thus presenting a relatively large ratio of lever arms as set out.

Referring to Fig. 3, a shaft 46 is provided to carry the sprocket wheel 38 and extends transversely of the housing 2 and is rotatably mounted in suitable bearings such as shown at 48. An extremity 50 of the shaft 46'has The other side of the table 2!} is provided provided thereon a permanent magnet 52 whereby the magnet rotates with the shaft. Provided on suitable supports 54, as may be seen in Fig. 5, are a pair of switches 56 and 58. These switches are of the type-which are magnetically responsive and will open and close according to the angular position of the magnet 52. Suitable switches for this purpose may be the type constituted by a pair of contacts including a-movable contact sealed in a glass bulb and wetted by mercury for better conductivity. The movable contact may be formed of .a magnetic material to respond to a changing magnetic field in accordance with the rotation of the permanent magnet 52. Such switches may be utilized in circuitry controlled by the perforated card sensing means for purposes to be brought out hereinafter.

Referring to Fig. 4, another magnetically responsive switch 60 is mounted on a support 62 extending from a side wall of the housing 2. A permanent magnet 64 is secured to a shaft which extends from a gear reduction transmission system 66 secured to the side wall of the housing. Depending from the table 20 is a shield 68 of magnetic material to prevent operation of the switch 60 by the permanent magnet 64 during certain portions of the cycle of operation of the perforated card sensing apparatus as will be explained in greater detail hereinafter. Fig. 2 shows a means for rotating the permanent magnet 64 in accordance with the movement of the table 20. This means comprises a rack 70 secured to the under surface of the bearings 26 and engaging a pinion 72 on the input side of the gear reduction transmission 66. The gear reduction ratio is so chosen so as to provide for a rotational velocity of the permanent magnet 64 to actuate or close the switch 60 at least once for each potential perforation on a card being sensed.

, The sensing elements for the cards are constituted by wire brushes 74. In Fig. 6B the wire brushes 74 are shown as being mounted in a support constituted by a pair of insulating members 76 secured by the threaded fastener 78 to the vertical guide 18. The brushes are flexible elements and extend through a right angle flexible support 80 also secured at one end to the guide 18 by the threaded element 78. Suitable means such as shown at 81 may be provided to electrically insulate the brushes 74 from support 80, as best seen in Fig. 6B. Connectors 82 on each of the brushes 74 are connected to a terminal board 84 secured to the vertical guide 18 above the supporting means 76.

In order to minimize stress on the sensing brushes 74, in accordance with our invention we provide a pair of vertically extending bearing supports 86, one on each side of the housing 2. A shaft 88 is mounted in the bearings 86 for rotation. A pair of lever arms 90 are fixedly secured on the shaft 88 by the set screws 92 for rotation therewith. An actuating lever 94 is fixedly secured to the shaft by the set screws 96 whereby when the actuating lever 94 is rotated, the shaft 88 and lever arms 90 will rotate therewith. A portion 98 of the angular support 80 extends forward and is secured to the lever arms 90 by the threaded fasteners 99. The construction is such that upon the rotation of the levers 90 in a clockwise direction as shown in the drawings, in response to the rotation of the actuating lever 94 and shaft 88 the flexible angular support 80 is rotated forward about its connection with the vertical guide 18 to raise the sensing elements or brushes 74 away from surface of the table 20 and a card 100 which may be thereon.

The means for rotating the actuating lever 94 comprises a push rod 102 movably secured by a bracket 103 to guide 18 and which carries a guide block 104 thereon. The guide block 104 is slideably mounted in a guide 106 secured to the sides of the housing 2. The forward end of the push rod 102 is provided with a bearing surface 107 engageable in a notch 108 in the lever 94. An unbalanced lever 110 is pivotally mounted to a side of the housing 2 and is provided with a forward extension 112. The actuating lever 94 is provided at its lower end with'a pair of shoulders 113 and 114 in which the forward extension 112 of the lever may engage. The back end of the unbalanced lever 110 is provided with a sloped camming surface 115 which is engageable with a camming member 116 carried by the table 20. A means for retaining a perforated card in a forward position after it has been sensed by the brushes 74 in this embodiment of the invention is constituted by a pair of spring fingers 118 secured to the vertical guide 18. Each spring finger 118 is provided with an upwardly directed portion 120 and a shoulder portion 122 which engages behind the card'as it comes forward on the table 20. The shoulder portion 122 is ground or machined to provide a sharp corner or edge that will not slip over a card 100.

In the operation of our invention, a plurality of perforated cards to be sensed are placed in the hopper 14. The motor 44 is energized to drive the table 20 in a forward direction through the medium of the sprocket wheel 38, slotted lever 30 and projection 32 on the table 20. As the table moves forward, the raised portion 21 engages the lowermost card in the hopper and carries it forward beneath the spring fingers 118. As the table moves forward, the sensing elements or brushes 74 will ride over the surface of the card 100 until a perforation appears therein. The brush will thereupon make con tact through such perforation with the table 20 which forms a part of an electrical utilization circuit as will be explained in greater detail hereinafter.

When the table 20 has completed its forward movement, all possible positions of card perforations have been scanned by the brushes 74. The table will then normally commence to move to the rear. The sensing elements 74 will have been lifted from the surface of the card 100 or table 20 by the means described briefly above and in greater detail hereinafter, and the spring fingers 118 will have dropped behind the rearward most portion of the card. The rearward movement of the table 20 causes the spring fingers 118 to engage the back edge of the card 100 and, in effect to push it from the surface of the table 20 into the hopper 12. The means for lifting the brushes 74 out of a card or table engagement position so that the rearward movement of the table will not subject them to unnecessary and harmful stressing is best seen in Figs. 6A, 63, 7A, 7B and 8. As the table 20 moves forward, as may be seen in Fig. 7A, the rearmost bearing 26 engaging on the shaft 28 will contact the guide block 104 on the push rod 102 moving the push rod 102 in a forward direction to rotate the actuating lever 94 in a clockwise direction. Upon the rotation of the actuating lever 94, the unbalanced lever 110 will pivot in a clockwise direction so that the forward extension 112 thereof will now be engaged with the shoulder 114 as distinguished from its normal engagement with the shoulder 113. This may best be seen by comparing Figs. 6A and 7A. In Fig. 6A, the bearing 26 has not reached its forwardmost position which occurs when the card 100 has been completely traversed by the brushes 74 Whereas in Fig. 7A it has and the operation described above has occurred. Fig. 6B illustrates the brushes 74 engaging the card 100 corresponding to the same position of the elements shown in Fig. 6A. In Figs. 7A and 7B, the clockwise rotation of the actuating lever 94 has rotated the shaft 88 clockwise and consequently the lever arms 90 are rotated. The lever arms 90 in response to their clockwise rotation have pulled the forward extension 98 of the angular support 80 forward raising the brushes 74 from the surface of the card 100 and/ or table 20. Inasmuch as the card 100 has moved completely forward, the spring fingers 118 have dropped behind it so that the shoulder 122 engages with the rear end of the card. At this point, the table commences a rearward movement, but the card is prevented from such movement by virtue of the engagement therewith with the spring fingers 1'18, and falls into the hopper 12. The apparatus is shown in its forward-most position in Fig. 2.

The brushes 74 are returned to engagement with the table 20 and for engagement with a card on the next forward movement of the table by the action responsive to the continued movement of the table to the rear. In this movement, the table carries the camming member 116 therewith which engages with the sloped surface 115 on the unbalanced lever 110 rotating this lever in a counterclockwise direction to move the forward extension 112 out of engagement with the shoulder 114 permitting the actuating lever 94 and lever arms 90 to rotate counterclockwise. The forward extension 112 is then re-engaged with the shoulder 113. The action of the actuating lever 94 rotating counterclockwise forces the push rod 102 in a rearward direction to a position whereby it can be engaged by the bearing 26 and moved forward on the next forward motion of the table.

The information stored in the perforated cards in the form of the perforations therein may be derived therefrom and utilized by the brushes 74 in any number of systems. In Fig. 10, there is shown one circuit for deriving such information and presenting it in the form of electrical signals for a utilization device. This circuit comprises a source of D.C. electrical potential 122 which is adapted to be connected to the coil 124 of a pulsing relay by means of a conductor 126 and the contacts of the magnetic responsive switch 60' to a ground connection 128. The source 122 is also connected through a conductor 130 and contacts 132 of the pulsing relay 124 and the normally closed contacts 134 of a read-complete relay having a coil 136 and armature 138 to the coil 140 of a data storing device such as a stepping switch. In other devices, the coil 140 may constitute the primary winding of a transformer. The read-complete relay is also provided with normally open contacts 142 and 144 while its coil 136 is connected in a conductor 146 through the coil 136 and conductor 148 and sensing element or brush 74. The brush 74 normally engages the upper surface of the card 100, but upon sensing a hole 149 thereon passes through to contact the table 21 which is grounded. A sealing-in circuit for the coil 136 is provided through a conductor 150, the contacts of switch 56 when closed, contacts 142 when closed, coil 136, contacts 144 when closed and ground 128.

As the table 20 starts its forward movement, the position of the magnetic shield 68 is such that it is interposed between the permanent magnet 64 and magnetically responsive switch 60. As the table continues its forward movement, the shield will move from between the magnet 64 and switch 60 at the same moment a card moves into a position wherein it begins to be sensed by the brushes 74. This will permit the switch 60 to be closed and opened repeatedly as the magnet 64 rotates so that the pulsing relay 124 is repeatedly energized to open and close the contacts 132. The repeated opening and closing of the contacts 132 supplies pulses to the coil 140 of the utilization apparatus. These pulses are supplied for each potential position of a perforation as determined by the ratio of the rotation of the magnet 64 to the movement of the table through the drive comprised by the rack 70, pinion 72 and transmission 66. If desired, the pulsing relay 124 may be eliminated and the contacts of the switch 60 substituted for the contacts 132 of this relay. Pulses will be supplied to the coil 140 until the brush 74 senses a perforation in the card 100 and engages therethrough with the grounded table 20. Under this condition, when the contacts 132 are closed, the pulse developed thereby will be efiected to energize the read-complete relay coil 136. The energization of the coil 136 opens normally closed contacts 134 and closes the normally open contacts 142 and 144 to complete the sealing-in circuit described above for the coil 136. The characteristics of the read-complete relay are so chosen that it will operate faster than a stepping switch operated by the coil to open the contacts 134 before the pulse developed by the closing of contacts 132 will be effective thereon. This action indicates that the information in the portion of the card being sensed by the particular brush 74 is complete. Continued movement of the card forward after the sensing of a perforation therein does not result in the transmission of pulses to the coil 140 as the contacts 134 remain open due to the energization of the coil 136. During the forward movement of the table 20 the contacts of switch 56 have remained closed, but as it moves to its most rearward position the magnet 52 rotates to a position whereby it is effective to open these contacts. The opening of the con tacts in the switch 56 breaks the sealing-in circuit for the coil 136 permitting the contacts 134 to close and the contacts 142 and 144 to open to condition the apparatus to derive information from the next succeeding card fed forward by the table 20.

In the circuit illustrated in Fig. 11, means are provided for a mode of operation wherein it is desired to sense perforations on a card and then have a time interval in which an operation may be carried out before a next card is sensed. In Fig. 11, those elements which correspond to the parts illustrated in Fig. 10 have been given the same reference numeral and their function is the same. In this embodiment, the driving motor 44 is connected from the source of potential 122 through a conductor 152 and the contacts of the switch 58, which are arranged to be closed while the table 20 is moving. As the table reaches the limit of its rearward movement, the permanent magnet 52 is effective to open the contacts of the switch 58 to stop the motor 44 whereby the table Will be maintained in the rearward position. A switch 154 is connected across the switch 58 and is adapted to be controlled by a switch control means 156, which switch control means may be manually operated or may be constituted by a machine controlled element indicating the end of a completed operation or by an adjustable timing apparatus effective at the end of a completed operation thereby re-energizing the motor 44 to cause it to propel the table 20 to commence another cycle of operations. The switch 154 will then reopen by the ac tion of the switch control means 156. The closing of the switch 154 causes the table 20 to move in a forward direction and the magnet 52 to close the switch 58 so that the switch again assumes control over the motor 44.

Although in accordance with the provisions of the patent statutes this invention is described as embodied in concrete form and the principle thereof has been explained together with the best mode in which it is now contemplated applying that principle, it will be under stood that the elements shown and described are merely illustrative and that the invention is not limited thereto since alterations and modifications will readily suggest themselves to persons skilled in the art without departing from the true spirit of this invention or from the scope of the annexed claims.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. In a perforated card reading machine, storage means for cards to be read, a table under said storage means, means mounting the table for reciprocating movement, said table having portions under said storage means in all positions of movement, and sensing elements engageable with said table and a card carried thereon.

2. In a perforated card reading apparatus, means for storing a plurality of cards to be read, a table under said storage means, means mounting said table for reciprocat ing movement, sensing elements disposed on one side of said storage means, said table being of such a length as to extend under said storage means in one extremity of its movement and under said storage means and beyond said sensing elements in the other extremity of its movement.

3. In a perforated card reading apparatus, a hopper storing a plurality of perforated cards to be read, a table under said hopper, means mounting said table for reciprocating movement, sensing elements disposed on one side of said hopper, said table having a first portion extending under said hopper at one extremity of its movement and under said sensing elements at the other extremity of its movement and a second raised portion extending on a side of said hopper away from said sensing elements at said one extremity of movement and under said hopper at said other extremity of movement.

4. In a perforated card reading apparatus, means for storing a plurality of cards to be read, a table under said storage means, means mounting said table for reciprocating movement, sensing elements disposed on one side of said storage means, said table being of such a length as to extend under said storage means in one extremity of its movement and under said storage means and beyond said sensing elements in the other extremity of its movement, and means to raise said sensing elements when said table is toward said other extremity of its movement.

5. In a perforated card sensing device, a support, a hopper mounted on said support for storing a plurality of cards to be read, means for sensing perforations in the cards, a table having a forward portion and a rearward portion, said table being mounted on said support for reciprocating movement, means provided on said rearward portion of said table for engaging a card and urging it toward said sensing means, said rearward portion of table being disposed rearwardly of the cards in said hopper when said table is at one extremity of its movement and said forward portion of said table being disposed under said hopper when said table is at said one extremity 10f its movement and under said sensing means in the other extremity of movement.

6. In a perforated card sensing device, a support, a hopper mounted on said support for storing a plurality of cards to be read, means for sensing perforations in the cards, a reciprocating table having a first portion extending under said hopper in one position of movement and under said sensing means in another position of movement, and circuit means including an element responsive to the movement of said table for deriving information represented in the form of perforations in the cards.

7. In a perforated card sensing device, a support, a hopper mounted on said support for storing a plurality of cards to be read, mean for sensing perforations in the cards, a reciprocating table having a first portion extending under said hopper in one position of movement and under said sensing means in another position of movement, circuit means for deriving electrical signals representative of the information contained in the perforations in said cards, said circuit means including an element effective to produce electrical signals when a card is in a position to be sensed by sensing means.

8. In a perforated card sensing device, a support, a hopper mounted on said support for storing a plurality of cards to be read, means for sensing perforations in the cards, a reciprocating table having a first portion extending under said hopper in one position of movement and under said sensing means in another position of movement, a circuit for developing electrical signals representative of the information stored in the cards, said circuit including switch means effective to produce said signals for each of the potential positions of a perforation in the card being sensed, and means to render said switch means ineffective unless a card is in a position to be sensed.

9. A perforated card sensing apparatus comprising a support, a hopper mounted on said support for storing a plurality of cards to be read, means mounted on one side of said hopper for sensing perforations in a card, a table mounted on said support for reciprocating movement and having a first portion extending under aid hopper when the table is in its most rearward position and under said sensing'means when the table is in its most forward position and having a second portion extending on the other side of said hopper when the table is in its most rearward position and under said hopper when the table is in its most forward position, a circuit for developing electrical signals representative of the information stored in the cards, said circuit including magnetically responsive switch means effective to control the circuit, magnet means for operating said switch means, and a magnetic shield effective to prevent operation of said switch means except when a card is in a position to be sensed.

10. A perforated card sensing apparatus comprising a support, a hopper mounted on said support for storing a plurality of cards to be read, means mounted. on one side of said hopper for sensing perforations in the cards, a table mounted on said support for reciprocating movement and having a first portion extending under said hopper when the table is in its most reaward position and under said sensing mean when the table is in its most forward position and having a second portion extending on the other side of said hopper when the table is in its most rearward position and under said hopper when the table is in its most forward position, a circuit for developing electrical signals representative of the information stored in the cards, said circuit including magnetically responsive switch means effective to control the circuit, a magnet for operating said switch means, means rotating said magnet at a speed whereby it closes said switch means for each potential perforation in a card, and magnetic shielding means effective to prevent said magnet from operating said switch means except when a card is in a position to be sensed.

11. A perforated card reader comprising a support, a hopper on said support for storing cards to be sensed, flexible sensing elements mounted on one side of said hopper, a reciprocating table mounted on said support and having a portion extending beneath said hopper when the table is in its most rearward position and beneath said sensing element when said table is in its most forward position, means carried on said table for engaging a card to be read and to urge it toward said sensing elements, rotatable lever means, means connecting said sensing elements to said rotatable lever means, and means engageable with said table when said table is in itsmost forward position to rotate said lever means in a direction to raise said sensing elements away from said table.

12. A perforated card reader comprising a support, a hopper on said support for storing cards to be sensed, flexible sensing elements mounted on one side o said hopper, a reciprocating table mounted on said support and having a portion extending beneath said hopper when the table is in its most rearward position and beneath said sensing elements when said table is in its most forward position, means carried on said table for engaging a card to be read and to urge it toward said sensing elements, rotatable lever means, means connecting said sensing elements to said rotatable lever means, a rotatable shaft mounted on said support and carrying said lever means, an actuating lever on said shaft, means engaging said actuating lever and engageable with said table in it most forward position to rotate said actuating lever, means for maintaining said actuating lever in its rotated position, and means for releasing said maintaining means as said table approaches its most rearward position.

13. A perforated card reader comprising a support, a hopper on said support for storing cards to be sensed, flexible sensing elements mounted on one sideof said hopper, a reciprocating table mounted on said support and having a portion extending beneath said hopper when the table is in its most rearward position and beneath said sensing elements when said table is in its most for- Ward position, means carried on said table for engaging a card to be read and to urge it toward said sensing elements, rotatable lever means, means connecting said sensing elements to said rotatable lever means, a rotatable shaft mounted on said support and carrying said lever means, an actuating lever on said shaft, means engaging said actuating lever and engageable with said table in its most forward position to rotate said actuating lever, means for maintaining said actuating lever in its rotated position, means for releasing said maintaining means as said table approaches its most rearward position, and circuit means for deriving electrical signals 5 is in a position to be sensed by sensing means.

References Cited in the file of this patent UNITED STATES PATENTS Ford Feb. 11, 1941 

